You CANNOT keep the Law, or the rituals, etc. for there is no Temple, no Altar, no burn offering, no High Priest, no Levitical order, etc., etc.
Therefore, if you do not accept WHO Jesus is and WHAT Jesus did, you will die in your sins.
You should read the book of Hebrews (written to Jews) and stop with "For our God is a consuming fire".
Chapter 13 is more toward Gentiles to remember all that Paul wrote to the Jews and not make the same mistake they made.
The New Testament tells us that God added (Gal. 3:17, 19) to the Law of Moses to the life of his people to teach them: the Law taught people about sin (Gal. 3:19, 22-23), and it taught people about Christ (Gal. 3:24). Now that Christ has come, the Law has been abolished (Gal. 3:25; Rom. 10:4): i.e. we do not need to follow the Law of Moses nowadays. Instead, nowadays we need to follow the Lord Jesus Christ himself (Gal. 6:2; Phil. 2:5; 1 Peter 2:21.
All written to Jews first and then because Israel rejected and continues to reject WHO Jesus is and WHAT He did, we Gentiles have a chance to enter into God's mercy. How awesome the God of Israel, how merciful the God of Israel, and how sad that Israel continues to reject Him. How sad that Israel has chosen to go through the tribulation, the great, and only then will realize WHO Jesus is and WHAT He did for them. How wonderful for those Jews who now accepts WHO Jesus is and WHAT He did and will not have to go through the tribulation, the great as Jesus proclaimed that it is coming to Jacob.
If I am not mistaken you said you WERE a Christian. A Christian will not place himself/herself under the Law again, for whoever keeps the whole law and yet stumbles at just one point is guilty of breaking all the Law.